白藜芦醇对大鼠糖尿病性白内障的治疗作用

Therapeutic effect of resveratrol on diabetic cataract in rats

目的探讨白藜芦醇对糖尿病性白内障大鼠晶状体的治疗作用。方法取45只成年健康sD大鼠[（300±5）朗采用随机数字表法将其随机分为正常对照组、糖尿病模型组和白藜芦醇治疗组，每组各15只。正常对照组给予常规饲料喂养，糖尿病模型组和白藜芦醇治疗组大鼠采用链脲佐菌素60mg／kg制作糖尿病模型，白藜芦醇治疗组成模后按400mg／kg体重给予白藜芦醇灌胃。分别于治疗后4、8和12周后观察3组晶状体混浊度的变化情况，同时检测晶状体内超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）、丙二醛（MDA）等酶活性的变化，并采用DNA缺口末端原位标记法（TUNEL法）检测各组各时段大鼠晶状体上皮细胞（LEC）凋亡率。组间数据两两比较采用t检验。结果4、8和12周时，正常对照组大鼠晶状体始终透明，白藜芦醇治疗组晶状体混浊度高于正常对照组，但与糖尿病模型组相比明显减轻。4、8和12周白藜芦醇治疗组晶状体混浊情况图像分析灰度值分别为27．5±2．2、34．4±1．8、46．4±5．1，均低于糖尿病模型组（t=24．063、53．411、54．027，均P〈0．05），但均高于对照组（t=-8．902、-31．567、-44．013，均P〈0．05）。上述各时间点白藜芦醇治疗组SOD活性和GSH—Px活性均高于糖尿病模型组（t=-145．738—-18．193，均P〈0．05），但低于对照组（t=11．388～95．746，均P〈0．05）；MDA活性均低于糖尿病模型组（t=33．027、29．623、40．976，均P〈0．05），但高于对照组（t=-14．920、-22．851、-39．992，均P〈0．05）。4、8和12周白藜芦醇治疗组大鼠凋亡晶状体上皮细胞数目分别为0．66±0．17、17．89±0．24、28．21±0．38，均高于对照组（t=-25．958、-77．897、-80．725，均P〈0．05），但均低于糖尿病模型组（t=101．729、45．940、167．104，均P〈0．05）。结论白藜芦醇可增加晶状体抗氧化酶活力并抑制晶状体上皮细胞的凋亡，从而延缓糖尿病性白内障的发生和发展。

Objective To investigate the therapeutic effect of resveratrol on diabetic cataract in SD rats. Methods Forty-five SD rats（weighted （300±5） g） were randomly divided by using random number table into normal control group, diabetic model group and resveratrol group, 15 in each group. Diabetic cataract was induced by streptozotocin（STZ） in diabetic model group and resveratrol group. No treatment was given to the rats in normal control group, diabetic model group. The 400 mg/kg resveratrol was administrated by gavage in resveratrol group. At the end of 4, 8 and 12 weeks after the treatment of resveratrol, eyeballs were harvested and cataract formation in all rats was recorded, meanwhile the activity of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, and the level of malondialdehyde（MDA） in lenses were measured respectively. And the apoptosis of lens epithelial cells was detected and statisticed using terminal deoxynucleotidy transferase mediated x-dutpnik end labeling（TUNEL） method. Data were compared between groups by using t test. Results At the end of 4, 8 and 12 weeks, lens of normal control group were transparent, lens opacity in resveratrol group was higher than those in control group, but was lower than those in diabetic model group. At the end of 4, 8 and 12 weeks, the grey value of lens in resveratrol group was 27.5±2.2, 34.4± 1.8, 46.4±5.1 respectively, and were all significantly lower than those in diabetic model group（t=24.063, 53.411, 54.027, all P〈0.05）, but were all markablly higher than those in control group（t=-8.902, -31.567, -44.013, all P〈0.05）. At the above-mentioned time points, the activity of SOD and GSH-Px were botn significantly higher than those in diabetic model group（t=-145.738-18.193, all P〈0.05）, but lower than those in control group（t=11.388-95.746, all P〈0.05）; the activity of MDA was lower than those in diabetic model group（t=33.027, 29.623, 40.976, all P〈0.05）, but higher than those in control group （t=-14.920, - 22.851, - 39.992, all P〈0.05）. At the end of 4, 8 and 12 weeks, the apoptosis rate of lens epithelial cells in resveratrol group were 0.66±0.17, 17.89±0.24, 28.21±0.38, respectively, which were higher than those in control group（t=-25.958, -77.897, -80.725, all P〈0.05）, but obviously lower in diabetic group（t=101.729, 45.940, 167.104, all P〈0.05）. Conclusion Resveratrol could increase the antioxidase activity, and inhibit the apoptosis of lens epithelial cells in diabetic cataract rats, thus delays the generation and development of catarac.